I hate to say it, but circumstances have arisen that force me to not be able to participate (though, I probably wouldn't have finished anyway). If anyone still wants an idea, here is mine, feel free to use it:

my idea is you play as a pilgrim with a blunderbuss trying to survive the onslaught of mutant turkeys by finding projectiles. Being a blunderbuss, you can have as many projectiles as you can find, but you use them all in one shot (more projectiles = more damage). So you only ever have one shot at a time, of course starting with nothing. Turkeys have a chance of either dropping a projectile (20%) , health (30%), or nothing (50%) when they die.